Foldable structures

ABSTRACT

A foldable structure which can be used as the basis for a wide variety of articles, such as furniture, office equipment, freight containers and portable buildings, is foldable between a generally flat form and an erected, three-dimensional form. A first pair of opposed frame units (10,11) are connected by at least one further frame unit (12), which is hingedly attached to one (11) of the pair of frame units and is hingedly and slidably attached to the other (10) of the pair of frame units, for example by means of swivel cleats (13). Further components are connected to one or both of the pair of frame units (10,11) so that such further components can be disposed in a folded-flat position adjacent to said pair of frame units (10,11) when the latter are in their collapsed state and can be disposed in a second, ready-for-use position in planes at an angle to the planes containing the frame units to which they are attached.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to foldable structures, which can be used as thebasis for a wide range of domestic furniture items, office equipment,workshop and industrial units, freight containers and portablebuildings, by way of example. An important principle in the constructionand operation of the foldable structures of the invention is the abilityto change a framework or foldable structure from a generally flat andessentially two-dimensional form into an erect three-dimensional form.

2. Description of the Prior Art

The present invention results from further development in the uses ofswivel cleats as the connections between the relatively hingeablecomponents of collapsible frameworks, such as are disclosed inGB-2055290B and GB-2179698B. These prior disclosures relate tocollapsible structures which incorporate such frameworks and to swivelcleats used in their construction.

It has now been discovered that foldable structures of improvedversatility and utility can be made on the basis of collapsibleframeworks of the kind mentioned above, which have additional componentsof the frameworks and with any panel units attached to or incorporatedin them. As will be made apparent below, the foldable structures of thepresent invention can include frame units, e.g. rectangular arrangementsof bars or rods, panels attached to frames or panels per se, andcarrying means for attachment to other frame units or other panels.

The foldable structures of the invention can be embodied in a widevariety of articles and systems, where there is a need for thestructures to be stored, transported and delivered in a flat conditionand then to be erected, in a very short time and very easily, into athree-dimensional configuration, to enable the articles or systems to beused.

SUMMARY OF THE INVENTION

It is an object of the invention to provide foldable structures whichare space-saving, in that they can be folded flat. The foldablestructures can be assembled quickly without the need for special tools,nuts, bolts or adhesives. Each foldable unit can be pulled into positionwith a concertina-like action to form a rigid structure. All thefoldable structures can be manufactured in wood, metal or composites,with durable, high quality finishes. The foldable structures are robust,and easily stored when not required for use.

Among the products which can be made with the foldable structures of thepresent invention are desks, cabinets, racking systems, kitchen units,tables, security cages for construction equipment, access towers forconstruction sites, sheds for gardens and general storage, outdoorfurniture and portable buildings for temporary or permanent use. Theseare examples only of the products which can be made with these foldablestructures.

According to one aspect of the present invention, a foldable structurecomprises a first pair of opposed frame units which are operativelyinterconnected by at least one further frame unit, which is hingedlyattached to one of the first pair of frame units and hingedly andslidably attached to or associated with the other of the first pair offrame units, wherein a further component of the foldable structure isconnected to at least one of the first pair of frame units by connectionmeans, whereby the further component can be disposed in a first,out-of-use folded position adjacent to the first pair of opposed frameunits when in their collapsed state and alternatively can be disposed ina second, ready-for-use position in a plane at an angle to the planecontaining the frame unit to which it is attached.

According to a further aspect of the present invention, a foldablestructure comprises at least a first pair of opposed frame unitsinterconnected by at least one further frame unit hingedly connected toone of the first pair of frame units and hingedly and slidablyinterconnected with the other of the first pair of frame units, whereinthe opposed pair of frame units are disposed generally vertically whenthe foldable structure is disposed in an erected, ready-for-useconfiguration, with relative sliding movement between one of the firstpair of frame units and the further frame unit or units interconnectingit with the other of the first pair of frame units taking place in anupward or downward vertical direction, and wherein a further componentarranged to define a generally horizontal portion of the structure whenin use is hingedly attached to one of the pair of opposed frame units byconnection means allowing relative movement therebetween as the foldablestructure is changed from a generally flat configuration to an erectedready-for-use configuration.

According to a further aspect of the invention, a foldable structurecomprises at least a first pair of opposed frame units interconnected byat least one further frame unit hingedly connected to one of the firstpair of frame units and hingedly and slidably interconnected with theother of the first pair of frame units, wherein the opposed pair offrame units are disposed generally vertically when the foldablestructure is disposed in an erected, ready-for-use configuration, withrelative sliding movement between one of the first pair of frame unitsand the further frame unit or units interconnecting it with the other ofthe first pair of frame units taking place as reciprocating movement ina generally horizontal direction, and wherein a further componentarranged to define a generally horizontal portion of the structure whenin use is hingedly attached to one of the pair of opposed frame units byconnection means allowing relative movement therebetween as the foldablestructure is changed from a generally flat configuration to an erectedready-for-use configuration.

Preferably, said at least one further frame unit is connected by swivelcleats to the adjacent frame unit of the opposed frame units.

Preferably, panel members are incorporated in or are attachable to eachof the frame units, whereby a structure comprising base, top, front,back and opposed side panel members can be collapsed into a generallyflat configuration while the front and back panel members remainsubstantially parallel to each other.

In order that the invention may be more readily understood,representative embodiments of various aspects of the present inventionare described below, by way of illustration only, in conjunction withthe accompanying drawings. In the drawings:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows in diagrammatic perspective view a foldable structureaccording to the invention comprising a number of rectangular frameunits or members, each frame member incorporating a mesh structure andserving for instance as part of a security or safety cage;

FIG. 1A shows a view of a security cage similar to that shown in FIG. 1,but without one or more of the members forming the front of the cage, toillustrate inter alia a modular principle by which larger structures canbe made;

FIG. 1B shows in diagrammatic view a plan of the foldable structure onFIG. 1 with the top removed, during transition from the collapsed to theerected state;

FIG. 1C similarly shows in detail how a top panel of the security cagesof FIGS. 1 and 1A can be hinged up into its ready-for-use position whenthe foldable structure has itself been erected;

FIG. 2 shows a plan view of the security cage of FIG. 1; and

FIG. 3 shows an elevational view of the top panel thereof;

FIG. 4 shows a detailed view of the top panel inside view, along theline of the arrows C--C in FIG. 3;

FIG. 4A shows, on an enlarged scale, the right-hand end portion of FIG.4;

FIG. 4B shows, also on an enlarged scale, the left-hand end portion ofFIG. 4;

FIG. 4C shows on the same scale a side view looking at FIG. 4B from theleft-hand end;

FIGS. 5A, 5B, 5C and 5D show a cabinet with shelf and cupboard,respectively in the fully collapsed flat state, with the top panelfolded up for use, with the front frame unfolding relative to the backframe, and in the fully-erected condition;

FIG. 6 shows in diagrammatic perspective view the framework structure ofthe furniture item of FIGS. 5A to 5D and its association with a backpanel;

FIG. 6A shows in diagrammatic perspective view a side panel forassociation with the foldable structures of FIGS. 5A to 5D and 6.

FIG. 7A shows a freight container according to the invention in afolded-down state;

FIG. 7B shows the container of FIG. 7A with the bottom and top unfolded;

FIG. 7C shows the container of FIGS. 7A and 7B with the front framebeing raised into place;

FIG. 7D shows the container in its fully erected state, and turned overthrough 90° as compared with FIGS. 7A to 7C;

FIG. 8A shows one module, in folded flat condition, suitable for use aspart of a building structure according to the invention;

FIG. 8B shows the module of FIG. 8A in a partially unfolded state,without doors; and

FIG. 9 shows an accommodation unit comprising a plurality of modulesaccording to FIGS. 8A and 8B.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to FIG. 1, a foldable structure comprises an opposedpair of front and back rectangular frame members, the front member beingindicated at 10 and the rear (back) member at 11. Each of the framemembers 10, 11 consists of opposed pairs of side uprights, aninterconnecting horizontal at the bottom and an interconnectinghorizontal at the top. The front and rear frames 10, 11 in the collapsedstate lie adjacent to one another, essentially flat and in the sameplane, and can be erected into the condition shown in FIG. 1 by themotion of an opposed pair of side frames 12 interconnecting them. Eachside frame 12 also consists of a pair of opposed side members connectedby bottom and top horizontals. Each side frame 12 is hingedly attachedto the rear frame 11 and hingedly and slidably attached to the frontframe 10, by means of swivel cleats 13, as shown most clearly in FIG.1B. The swivel cleats may be of the form shown and described inGB-2179698B. A pair of rectangular sub-frames 14 are provided, as a pairof front doors, and are hingedly attached in normal manner, by means oftheir outer side members, to the side members of the front frame 10. Inorder to form a security cage, wire mesh panels 15 are secured as bywelding at their edges to appropriate parts on the frame members, whichtherefore are also made of metal capable of being welded to the wire ofthe panels 15. The panels 15 are secured to the front, rear and sideframes 10, 11, 12 and to the sub-frames 14. Generally, it is unnecessaryto enclose the base of the folding structure, particularly if this isdesigned to be fixed to the ground.

In order to enclose the top of the foldable structure, a top frame 16 ishingedly and displaceably attached, for instance at its rear framecomponent 17, to the top horizontal of the rear frame 11. For thispurpose, each corner of the top frame 16 is provided with a dependentlug 18 having a vertical slot 19 formed in it, i.e. in a directiongenerally at right-angles to the plane of the top frame 16. Each slot 19in one of the opposed pair of lugs 18, thus provided one at each rearcorner of the top frame 16, is fitted over a pin 20, described in detailbelow and secured to the upper portion of the side members of the rearframe 11. The top frame 16 also includes a mesh panel 21, similar to themesh panels 15. The foldable structure shown in FIG. 1A is similar tothat shown in FIG. 1, except that the sub-frames 14 forming the doorsare omitted to allow the interior construction to be seen and also toserve as a second or subsidiary modular foldable structure forassociation with the first if required. For instance, a rear panel neednot be provided on the foldable structure of FIG. 1.

As best shown in FIG. 4, the top frame 16 incorporates an L-sectionmember 22 at its front, which overlies the sub-frames 14 when the doorsare closed. With the foldable structures illustrated in FIGS. 1 to 4Cinclusive, it will be appreciated that the opposed front and rear frames10, 11, forming a first pair of opposed frames, generally remain uprightand parallel to one another as they move from the face-to-face contactposition, i.e. when the structure is folded flat, into the erected andmutually-spaced condition, i.e. when the structure is opened out readyfor use. The side frames 12 are hingedly attached to the rear frame 11and thus pivot about essentially vertical axes, while the swivel cleats13 hingedly and slidably interconnecting the side frames 12 with thefront frame 10 also hinge about vertical axes, as the folding structureis changed from one configuration to the other.

By way of contrast, in the foldable structure illustrated in FIGS. 5A to5D, 6 and 6A, the axes about which hinging of the frames forming thefoldable structure takes place are essentially horizontal. The foldablestructure shown in FIGS. 5A to 5D, 6 and 6A thus comprises a front frame30 and a rear (back) frame 31 which are normally disposed in verticalplanes. When the structure is folded flat (FIG. 5A), the frames 30, 31are in face-to-face contact and are essentially located in the samevertical plane.

As most clearly shown in FIG. 6, the front frame 30 is connected to therear frame 31 by a top frame 32, consisting of an opposed pair of sidemembers 45 which are hinged at their front ends to the uprights 46 ofthe front frame 30 and which are slidably and hingedly connected to theuprights 46 of the rear frame 31 by means of two swivel cleats 33. Therear ends of the side members 45 are joined by a rear rod 44 which, whenthe top frame 32 reaches its horizontal position, engages behind springclips 48 attached to the top of the rear frame 31 and designed to holdthe frames in the erected condition. Similarly, the front and rearframes 30, 31 are interconnected by a bottom frame 43 mounted similarlyto hinge at the front and hinge and slide at the rear. The bottom frame43 supports a bottom panel 49. As the cabinet shown in these drawings ischanged from its flat configuration shown in FIG. 5A to the erectedconfiguration shown in FIG. 5D, the top and bottom frames 32, 43 hingerelative to the front and rear frames 30, 31, as best shown in FIG. 5Cand FIG. 6. The cabinet is completed by means of a rear panel, a toppanel 36, hinged to the top of the rear frame 31 by means of lugs 38containing slots 39 which engage over pins 40, and an opposed pair ofside panels 35, an inside view of one of which is shown in FIG. 6A. Eachside panel 35 includes a Z-section angle member 50 and an L-sectionangle member 51, which respectively engage with the side members 45 andthe adjacent edge of the bottom panel 49, when the foldable structurehas been fully erected.

Referring now to FIGS. 7A to 7D, there is shown a foldable structuredesigned as a freight container. FIG. 7A shows the container in asubstantially fully folded-down position. The container comprises a topframe 60, a bottom frame 61, a rear frame 62 and a front frame 63. Thetop and bottom frames 60, 61 are each provided at each end with flangeplates 64 which are each provided with a slot 65 which engages with apivot pin 66 fitted to the rear frame 62. By this connection means, whenthe top and bottom frames are unfolded, as indicated by the arrows inFIG. 7B, into their erected positions, the connection permits pivotablemovement and translational movement to be effected between the top andbottom frames on the one hand and the rear frame on the other hand.

FIG. 7C shows the next stage in the process of erecting the container.Here, the front frame 63 has been raised most of the way towards itsfinal position. When it is fully raised, security pins 67 on the frontframe engage in corresponding holes 68 in the longer members of the topand bottom frames 60, 61. As can be seen from FIG. 7C, as the frontframe 63 is raised in the direction of arrow 69, two side frames,indicated generally at 70, are moved towards an erected position inwhich they complete the box formation of the container. The arrow 71indicates the direction of movement of one side frame 70. The sideframes 70, in a manner analogous to the earlier embodiments, have theirshorter side pieces 72 hingedly connected to the rear frame 62 at oneend and hingedly and slidably attached to the front frame 63 at theirother ends, again by swivel cleats 73. In this way, as the front frameis raised, the two side frames 70 move from their folded flat positionto a position in which they complete the sides of the container.

FIG. 7D shows the container fully assembled. From the position shown inFIG. 7C the container is turned through 90° so that the top frame 60 isnow uppermost. The side frames 70 are secured to the front frame 63 whenthe swivel cleats 73 have reached their final positions. This can be bymeans of spring clips for example. As shown in FIG. 7D the container hassheet steel cladding indicated generally at 74 on the front frame andhas a door 75 fitted to the one side frame. The container is preferablymanufactured from steel, using steel tube and steel sheet components.However, other materials could be used.

Referring now to FIGS. 8A and 8B, there is shown a module, indicatedgenerally at 80, which is shown in its folded flat condition in FIG. 8A.FIG. 8B shows the module in a partially unfolded state, without doors.The arrows indicate the direction of unfolding of the component parts.As shown in FIG. 8B, the module comprises a front frame 81, a rear frame82, and a pair of side frames 83 which, as in the embodiments describedabove, are hingedly connected to the rear frame and are hingedly andslidably connected to the front frame 81 by swivel cleats 84. The basicframe structure 81, 82, 83 is provided with a further component 85,which here constitutes a top panel and which as shown in FIG. 8A foldsdown flat against the other parts of the structure. The top panel 85 isconnected to the rear frame 82 by a slot and pin connection whichpermits pivotal and translational movement of the two parts relative toeach other as the structure is unfolded.

FIG. 9 shows a building structure which can be made up from a pluralityof the modules 80 shown in FIGS. 8A and 8B. The erected modules arepositioned side-by-side and are then connected to each other by suitablemeans, for example by using over-centre clips. Alternatively, themodules can be bolted together. The modules can be of the same ordifferent designs, with a number of different features being shown inFIG. 9. These include a pull-down flap 86 and a wire mesh door 87.Because the individual modules are complete in themselves and have noloose nuts, bolts, etc., it is possible to erect the individual modulesfrom the fully folded flat position to the fully erected position inabout 12 seconds, with the subsequent connection together of theindividual modules taking a matter of a few minutes. It is thus possiblevery quickly and easily to provide units of this nature for permanent ortemporary accommodation for example and for storage purposes.

As a further development of the arrangement shown in FIG. 9, one candesign a structure which is not "linear" but which extends in two ormore directions at an angle to each other. This is achieved byconnecting two or more sets of such modules by corner modules whichcomprise a simple triangular framework having a vertical hingeconnection at one corner of the triangle and swivel cleats between twoof the sides, thus permitting the triangular module to be folded flat orerected into the triangular configuration. The triangular module then ispositioned between two "linear" arrays of modules 80.

I claim:
 1. A foldable structure comprising:a front frame; a top frame;a back frame being parallel to said front frame; a first side framehingedly attached to said front frame and by a first pair of slidableand hingeable swivel cleats; a second side frame hingedly attached tosaid front frame and slidably and hingedly attached to said back frameby a second pair of swivel cleats, said first side frame and said secondside frame being adapted for simultaneous movement so as to expand thefoldable structure into an erected box configuration when said firstside frame and said second side frame are moved parallel to each otherand to collapse the foldable structure into a flat collapsedconfiguration when sliding and hinging ends of said first side frame andsaid second side frame are moved toward each other; connection means forconnecting said top frame to one of said front frame and back frame whenthe foldable structure is in said flat collapsed configuration, said topframe being movable to be at right angles to said front frame and beingdisposed on said front frame so as to prevent movement of said front andback frames relative to each other and to form a top to the foldablestructure when the foldable structure is in said erected boxconfiguration; and a plurality of panels, one of each being attached tosaid front, back, first side, second side, and top frames, said panelsenclosing said frames such that the foldable structure is an enclosedrectangular container when in said erected box configuration and saidfront frame is vertically disposed whereby the foldable structure can becollapsed into a flat collapsed configuration when said panels areattached to said frames.
 2. A foldable structure as recited in claim 1further comprising:a bottom frame having a panel attached thereto andenclosing said bottom frame, said bottom frame being connected to one ofsaid front frames and said back frame by said connection means, saidbottom frame being parallel to said front frame and said back frame whenthe foldable structure is in said flat collapsed configuration, saidbottom frame being movable to be at right angles to said front frame andbeing adjacent to said back frame when the foldable structure is in saiderected box configuration so as to form a bottom to the foldablestructure such that the foldable structure is completely enclosed on allsides when the foldable structure is in said erected box configuration.3. A foldable structure as recited in claim 2, wherein said connectionmeans permits relative pivotal movement and relative translationalmovement of said top frame and said bottom frame with one of said frontframe and said back frame.
 4. A foldable structure as recited in claim3, wherein said connection means includes interengaging pin and slotcouplings.